Propeller



Sept. 8, 1931. c. H. A. s. bos s GALLO PRQPEIQLE R 'Filed ma 22, 1950 INVENTOR CfH/Zfi dos 53/2205 627110.

ATTORNEY Patented Sept. 8, 1931 UNITED STATES PATENT OFFICE CARLOS HORACIO AMARO SALGUEIBO nos SANTOS GALLO, OI MARINE-A GRANDE, PORTUGAL PROPELI'EB Application filed May 22, 1930, Serial No. 454,792, and inPortugal January 21, 1930.

This invention relates to an improved propeller for use in propelling ships, submarines, torpedos, automobiles,- aeroplanes, dirigibles and other vessels, the object of the invention being to provide an improved propeller which is especially adapted to be used on the bow or the front end of the vessel and which is of maximum efliciency in the propulsion of the vessel and is capable of being operated at a higher velocity than it has heretofore been possible to rotate propellers with a minimum expenditure of power.

With the above and other objects in view, the invention consists in the construction, combination and arrangement of parts hereinafter described and claimed.

In the accompanying drawings Figure 1 is a front elevation or plan view of a propeller constructed in accordance with my invention.

Figure 2 is a side elevation of the same, looking at the right of Figure 1.

In the construction of my improved propeller I provide a conical or substantially conical hollow hub 1, the diameter of the base of which exceeds the length at the central axis thereof. The conical hub is arranged with a plurality of blades or vanes 2 which may be six in number,'according to the size of the propeller, the uses in which it is to be .employed or the rate of the speed of revolution thereof and other conditions, and shown in the present instance as three in number spaced equal distances about the hub. Each blade is substantially of triangular shape in elevation from the front end to the rear end or base and having its greatest width at the base or connection with the hub and pointed or convergin toward the front end, the under surface ing substantially plane and arranged at the juncture thereof with the base, as at 3, to extend at an angle of not more than 45 degrees with respect to the axis of the hub with the outer surface extending in a plane tangential to the outer surface of the hub and slightly convex in cross section, and the blade being of greatest thickness at the base and gradually decreasin in thickness to the free end. The free en of the blade extends beyond the contour of the hub with the front or leadin edge arranged at an angle of about egrees relative to a line perpendicularly intersecting the axis of the hub and the base of the blade, viewing the ropeller in plan as shown in Figure 1, said ege of the blade commencing at a peripheral portion of the hub within and spaced from the apex of the core of the hub, as at 6,-and inclining upward with said edge at the extremity of the blade terminating substantially in the plane of the apex of the hub. The outer or following edge of the blade is curved in an upward direction from the base of the hub, as shown at 4, and is in an arc eccentric to the axis of the hub, as

viewed in plan in Figure 1, and said curve havlng a radius greater than the radius of the hub and merging with the hub tangential to the peripheral surface and base thereof, as at 5.

It will be observed on reference especially to Figure 2, that the outer edges of the blades or vanes diverge rearwardly to the extreme diameter of the base of the hub, each blade being broadest at its base end and tapering to its free end. The blades are arranged with their front straight edges commencing at the peripheral portion 6 of the hub spaced somewhat to the rear of the extreme front end or apex of the conical hub, and the inner edge of each blade where it is united to the hub is curved and disposed somewhat spirally from the point 6 to the base or rear end of the hub, the outer edge of each blade being curved and, as before stated, converging rearwardly to the periphery of the hub base.

In the operation of my improved propeller, the conical hub thereof displaces the water or air outwardly and radially, and minimizes friction of the water or air against the bow of the aquatic vessel or front end of the air vessel, as the case may be, and the While I have herein shown the preferred form of my invention, it is to be understood that changes may be made in the form and proportion of the various parts without de- 5 partin from the spirit of the invention as define in the appended claims.

Having thus described my invention, I claim:

1. In a propeller, a conical hub having. a

diameter at the base greater than the length, and blades equi-distantly spaced about the same, each blade beingof triangular shape with its greatest width at the juncture of the blade with the hub and converging toward the free end and being of a length to extend beyond the contour of the hub, the under surface of the blade being substantially plane and at the juncture thereof with the hub extending at an angle of not more than 45 degrees with respect to the axis of the hub, and theouter surface of the blade being slightly convexed in cross section and extending in ipklane tangential to theouter surface of the 2. A propeller as claimed in claim 1,wherein the leading edge of the blade extends at an angle of approximately 60 degrees relative to a line intersecting the axis of the hub and base of the blade, and the following edge of the blade being curved and extending in an arc eccentric to the axis of the hub and having'a radius greater than the radius of the hub and merging with the hub tangential to the base thereof.

3. A propeller as claimed in claim 1, wherein the leading edge of the blade extends at an angle of approximately 60 degrees relative to a line intersecting the axis of the hub and base of the blade, said edge commencing 40 at a point within and spaced from'the apex of the cone of the hu and inclining upward and at the extremity of the blade terminating'substantially in the plane of the apex of the hub, the following edge of the blade being curved upwardly from the base of the hub and arran ed in an arc eccentric to the axis of the hu and merging with the hub tangential to the base thereof.

In witness whereof I afiix mysignature.

CARLOS HORACIO AMARO SALGUEIRO do: SANTOS GALLO. 

